Recommend reconsidering the 80% chance that Omicron will displace Delta.
Appears that Omicron and Delta will co-exist. Prior Delta infection clearly does not provide much protection against Omicron infection. Converse is likely, as well.
Up until now Variant-share has been winner-take-all. From now on we will have at least two.
"In an even better world than that, we’d have run challenge trials the moment Omicron was detected"
I personally would have spent the first week of December figuring out how to home-brew an Omicron-tailored booster if I were at-risk.